A group of parliamentarians plans to lodge a legal appeal in an attempt to secure a European court ruling on Brexit.
The politicians believe the UK Parliament could unilaterally stop the UK leaving the EU if the final Brexit deal is deemed unacceptable by the Commons.
They want a definitive ruling from the European Court of Justice (CJEU) on whether the withdrawal process triggered under Article 50 can be halted by the UK on its own, without prior consent of the other 27 EU member states.
The group took its fight to the Court of Session in Edinburgh but on Tuesday Judge Lord Doherty turned down a bid to have a full hearing on whether to refer the question to the Luxembourg Court, ruling the issue is "hypothetical and academic", and that he is "not satisfied the application has a real prospect of success".
Now campaigners have announced plans to appeal against his ruling to the Inner House of the Court of Session.
Two of the original group of seven have withdrawn - the SNP's Joanna Cherry QC and Liberal Democrat Christine Jardine - while director of the Good Law Project, Jo Maugham QC, which has backed the crowdfunded legal action, has been added.
The remaining five members are Green MSPs Andy Wightman and Ross Greer, SNP MEP Alyn Smith and Labour MEPs David Martin and Catherine Stihler.
In a statement, Mr Maugham said they believe the judge's decision was "flawed".
He added: "Establishing that, alongside the political route to revocability there is a legal route, is vital in the national interest.
"If Parliament chooses not to withdraw the Article 50 notice then no harm is done by asking now the question whether it has that right.
"But if Parliament does come to want to withdraw the notice, knowing it has the right to do so serves the national interest.
"It improves the bargaining position of the UK, it ensures we retain the opt-outs and rebates that we presently enjoy, and it places the decision entirely in the hands of the UK's Parliament and - if it chooses - its people."
Aidan O'Neill QC, representing the politicians, previously asked for the case to proceed through the Scottish court, arguing there was a genuine dispute between the two sides as to the proper interpretation of Article 50 which the court required to resolve.
David Johnston QC, for the UK Government, insisted the application has no real prospect of success and that there was "no live issue" for the court to address.
The policy of the UK Government is that the notification under Article 50 will not be withdrawn, he said.
Finding in favour of the Government, Lord Doherty said: "Given that neither Parliament nor the Government has any wish to withdraw the notification, the central issue which the petitioners ask the court to decide - whether the UK could unilaterally withdraw the Article 50(2) notification - is hypothetical and academic.
"In those circumstances it is not a matter which this court, or the CJEU, require to adjudicate upon."